On Thu, Aug 09, 2018 at 01:58:05AM -0400, Eric Sunshine wrote: > On Wed, Aug 8, 2018 at 6:50 PM Jeff King <p...@peff.net> wrote: > > On Tue, Aug 07, 2018 at 04:21:31AM -0400, Eric Sunshine wrote: > > > +# Swallowing here-docs with arbitrary tags requires a bit of finesse. > > > When a > > > +# line such as "cat <<EOF >out" is seen, the here-doc tag is moved to > > > the front > > > +# of the line enclosed in angle brackets as a sentinel, giving "<EOF>cat > > > >out". > > > > Gross, but OK, as long as we would not get confused by a line that > > actually started with <EOF> at the start. > > It can't get confused by such a line. There here-doc swallower > prepends that when it starts the swallowing process and removes it add > the end. Even if a line actually started with that, it would become > "<EOF><EOF>cmd" while swallowing the here-doc, and be restored to > "<EOF>cmd" at the end. Stripping the "<EOF>" is done non-greedily, so > it wouldn't remove both of them. Likewise, non-greedy matching is used > for pulling the "EOF" out of the "<...>" when trying to match against > the terminating "EOF" line, so there can be no confusion.
Thanks. I figured you probably had thought of that, but it seemed easier to ask than to wade through the sed code (I do feel like a bad person to give that answer, because IMHO one of the key things that makes open source work is a willingness to dig in yourself rather than asking; but I am making an exception for this sed code). > Yeah, I was going with the tighter uppercase-only which Jonathan > suggested[1], but I guess it wouldn't hurt to re-roll to allow > lowercase too. > > [...] > > No. I've gotten so used to \EOF in this codebase that it didn't occur > to me to even think about 'EOF', but a re-roll could add that, as > well. Thanks. I could take or leave such fixes, since I think our style discourages both, so I'll leave it up to you whether you want to pursue them. -Peff
